1. Field of the Invention
An orotracheal intubation guide simplifies the process of passing an endotracheal tube through a patient's mouth and larynx, and into the trachea. Orotracheal intubation is a common medical procedure that enables mechanically ventilated respiration, delivery of anesthesia to a patient's lungs, protecting patency of a patient's airway; an orotracheal guide can also be diagnostic visualizations such as bronchoscopy, operative procedures to the airway, and other diagnostic, surgical, and therapeutic procedures. When orotracheal intubation is performed improperly (e.g., producing an unrecognized esophageal intubation), the associated complications will rapidly lead to injury or death of the patient.
2. Description of the Related Art
Orotracheal intubation is commonly performed on an unconscious patient, or a patient under general anesthesia, using direct laryngoscopy, i.e., a laryngoscope is used to obtain a view of the glottis and an endotracheal tube is then inserted through the vocal cords under direct vision. Orotracheal intubation is commonly performed on a conscious patient using local anesthesia and direct laryngoscopy. Intubation of a conscious patient ensures ventilation and oxygenation even in the event of a failed intubation, and is preferred if difficulties are anticipated.
To minimize risks of injuring the vocal cords, of esophageal intubation, etc., various types of orotracheal intubation guides have been developed for use during intubation. Even under direct laryngoscopy, placement of a tube through the epiglottis and glottis is challenging, especially for those with little or infrequent intubation experience; “blind intubation” (not under direct vision) elevates risk of injury substantially. Airways compromised by collapse, tumors, folds, obesity, etc., also elevate risk of injury by intubation. Commonly available intubation guides, such as intubation stylets (e.g., U.S. Pat. No. 6,164,277 to Merideth, U.S. Pat. No. 5,773,241 to King, and U.S. Pat. No. 5,235,970 to Augustine), arcuate blades (e.g., U.S. Pat. No. 4,694,826 to Chester), spouts (e.g., U.S. Pat. Nos. 6,672,305 and 5,743,254 to Parker), and tubes (e.g., U.S. Pat. Nos. 5,203,320, 5,042,469, and 4,832,020 to Augustine) are not adjustable to a patient's specific oral conformation. “Oral conformation” means herein the three dimensional shape and structure of the upper respiratory tract excluding the nasal cavity; particularly the shape, structure, and relationship among the anterior maxillary arch, the hard and soft palate, pharynx, and larynx. Flexible bronchoscopes, laryngoscopes, and other endoscopes used for direct visualization of the orotracheal passage are herein individually called a “bronchoscope” and collectively called “bronchoscopes”. Bronchoscopes can be navigated through body passages using means and methods known in the art. “Proximal” means at or in the direction of the exterior opening of a subject's mouth. “Distal” means in the direction of a subject's lungs through the passage comprising the oral cavity, pharynx, larynx, and trachea; this “oral tracheal” passage is called the “orotracheal passage”. As used herein, “patient” and “subject” are synonymous.
Existing art devices (collectively including traditional airway devices and newer endoscopic airway devices) take the approach of giving the operator greater manipulative control over a bronchoscope, or combination of coaxial tube and bronchoscope, rather than orienting the guide based on the unique oral conformation of a given patient. Existing art devices often increase the level of skill required in orotracheal intubation, since the operator is manually and concurrently controlling at least an intubation tube and intubation guide, and often a bronchoscope, all of which are “floating untethered” within the oral cavity.
A recognized, but unsolved problem, in the intubation of conscious patients is avoiding a conscious patient's “gag reflex” during intubation. The “gag reflex” is triggered by pressure on the distal surface of the tongue; having to cope with a patient's gagging makes intubation much more difficult, especially when the operator must concurrently manipulate an endotracheal tube, a bronchoscope, and an intubation device. All known traditional airway devices, such as the Berman Intubating Pharyngeal Airway (Sun-Med, Inc., Largo Fla.), and all known endoscopic airway devices, such as the Ovassapian Fiberoptic Airway (Hudson RCI, Research Triangle Park, N.C.), contact and depress the distal surface of the tongue, which usually causes a gag reflex in a conscious patient. The gag reflex can be triggered not only upon intitial placement, but also during manipulation of the airway device to advance a bronchoscope down the airway. The gag reflex significantly, and undesirably, raises the risk factors in intubation of conscious patients, since the uncontrolled movement of the bronchoscope can damage a patient's vocal cords, cause the patient to bite the bronchoscope or endotracheal tube, or simply reduce the probability of successful intubation.
Existing art airway devices, since they rest on the tongue, can also easily deviate from the midline of the oral cavity, which deviation makes a midline approach to the vocal cords with a flexible bronchoscope more difficult. Existing art, devices are obtrusive, unstable, poorly tolerated in the awake patient, require a skilled operator, and necessarily increase the risk of injury to unconscious patients and to conscious patients.
There is demand for an intubation guide that adjusts to the specific oral conformation of a patient and does not require the operator to manually and concurrently control both the intubation tube and the intubation guide. The technical problem to be solved is to provide an intubation guide that adjusts to the oral conformation of a given patient and is removably affixed in a patient's oral cavity, and that does not rest on or otherwise rely on a patient's tongue for support, thereby allowing an operator to devote the operator's entire attention to advancing the endotracheal tube and/or bronchoscope down the orotracheal passage without manually holding a guide in position, and easily remove the guide when desired. A second technical problem to be solved is to provide a means of allowing a lower skilled operator, e.g., an operator who does infrequent intubations, a higher success rate of intubation without inducing a gag reflex in a patient and of maintaining a mid-line entry of the endotracheal tube and/or bronchoscope. The solution to these technical problems would require less skill to use, would not trigger the gag reflex in conscious patients, would consistently provide midline approaches to the vocal cords of a patient, and would be cost competitive with, and more accurate than, existing intubation guides.